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How Do Demographic Trends Change? the Onset of Birth Masculinization in Albania, Georgia, and Vietnam 1990–2005

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How Do Demographic Trends Change? the Onset of Birth Masculinization in Albania, Georgia, and Vietnam 1990–2005 Christophe Z. Guilmoto, Nora Dudwick, Arjan Gjonça and Laura Rahm How do demographic trends change? The onset of birth masculinization in Albania, Georgia, and Vietnam 1990–2005 Article (Accepted version) (Refereed) Original citation: Guilmoto, Christophe Z. and Dudwick, Nora and Gjonça, Arjan and Rahm, Laura (2017) How do demographic trends change? The onset of birth masculinization in Albania, Georgia, and Vietnam 1990–2005. Population and Development Review. ISSN 0098-7921 DOI: 10.1111/padr.12111 © 2017 Wiley Periodicals, Inc This version available at: http://eprints.lse.ac.uk/85635/ Available in LSE Research Online: November 2017 LSE has developed LSE Research Online so that users may access research output of the School. Copyright © and Moral Rights for the papers on this site are retained by the individual authors and/or other copyright owners. Users may download and/or print one copy of any article(s) in LSE Research Online to facilitate their private study or for non-commercial research. You may not engage in further distribution of the material or use it for any profit-making activities or any commercial gain. You may freely distribute the URL (http://eprints.lse.ac.uk) of the LSE Research Online website. This document is the author’s final accepted version of the journal article. There may be differences between this version and the published version. You are advised to consult the publisher’s version if you wish to cite from it. How Do Demographic Trends Change? The Onset of Birth Masculinization in Albania, Georgia and Vietnam in 1990–2005. CZ Guilmoto, N. Dudwick, A. Gjonça and L. Rahm Abstract: While the rapid rise of the sex ratio at birth in Asia and Eastern Europe is well documented, the conditions surrounding its onset are poorly understood. Was the increase a response to factors determining prenatal sex selection or was it triggered by contingent events? In this paper, we examine the timing of the rise in the sex ratio at birth in Albania, Georgia, and Vietnam, three countries characterized by different social, political and economic conditions in 1990-2005. We take advantage of unique microdata to identify turning points in birth masculinity trends in each of these countries. Thus, the rise in the SRB appears to have clearly started in January 1992 in Georgia, during the first trimester of 1997 in Albania, and in August 2003 in Vietnam. We relate the onset of birth masculinization to various contextual events such as economic and political crisis, significant policy changes and fertility decline. The paper concludes with a discussion on the respective role of triggers of instant demographic change and of more structural factors affecting reproductive choices. 1 How Do Demographic Trends Change? The Onset of Birth Masculinization in Albania, Georgia and Vietnam in 1990–2005. 1. Introduction The theory of demographic transition assumes the gradual move from a pretransitional equilibrium of birth and death rates to a new equilibrium resting on lower vital rates. While this model remains largely correct, research on more than two centuries of demographic change in various settings has pointed to a significant number of variants and departures from the model. For instance, the fertility transition proved to be a rather complex demographic transformation since the secular decline was often preceded by a short-term rise and started from different high-fertility levels (Dyson and Murphy 1985) and was at times followed by unexpected stalls and rebounds as in postwar Europe (Van Bavel and Reher 2013), Southeast Asia (Hull 2012), sub-Saharan Africa (Shapiro and Gebreselassie 2013), or Central Asia (Spoorenberg 2015). In comparison, the evolution of the sex ratio at birth (SRB) appears less complicated. The SRB has remained stable over centuries, oscillating around 104–106 male births per 100 female births ever since it was first measured in 16th century England (Fellman 2015). The variations in birth masculinity by 1 or 2 percentage points are mostly inconsequential and due to random fluctuations or to lesser- known biological or compositional factors.1 It is only in a few countries of Asia and Eastern Europe that a significant rise in birth masculinity has emerged since the 1980s as people increasingly resorted to prenatal sex selection. In countries ranging from Albania to Vietnam, SRB levels have risen over the last three decades above 110 or 115 male births per 100 female births, leading to a long-term process of demographic masculinization. In some regions, the SRB stabilized to a plateau level while in some other regions such as South Korea, it has come back to a normal level, pointing to a cyclical trend in SRB changes (Guilmoto 2009). The increase of birth masculinity in affected countries appears therefore to be recent and well documented by census and birth registration series. Yet, changes in the SRB are still imperfectly 1 Examples abound of countries with reliable birth registration statistics in which the sex ratio at birth has for instance crossed 108 in several years such as Bulgaria (1997) Estonia (2005, 2006), Greece (2001) or Slovenia (1998, 2001). Data used here are from Eurostat. On the natural sex ratio at birth and its variations, see Chahnazarian (1988) and James (2009). 2 understood and its future course difficult to predict. The basic issue of the onset of the masculinization of births remains particularly unclear, with two lingering questions: When did the sex ratio at birth start departing from natural levels, and what type of factors or events set the change into motion? These questions first relate to the dating of the rise of birth masculinity. As argued by Van Bavel and Reher (2013) about the baby boom in America, it is crucial to properly identify the date of the onset before examining its contextual factors. Unlike the onset of the fertility transition— commonly identified as the period when total fertility rates (TFR) fall lastingly by more than 10 percent—there is no recognized threshold for spotting a rise in the SRB. However, the examination of yearly trends in East Asian and Eastern European countries suggests that once destabilized, the SRB tends to increase steadily until it reaches a new equilibrium level, usually in a range of 110-125 male births per 100 female births. Since there is indeed a beginning to the observed rise, it seems therefore legitimate to explore its potential determinants. The overall impact of a late or early onset of birth masculinization in itself is not without consequences. Had for instance Vietnam’s sex ratio at birth started to rise ten years earlier–a perfectly feasible event in view of its low fertility and entrenched son preference–, the country would have today 600,000 more surplus males.3 The issue of the onset of high birth masculinity touches on our understanding of the process of demographic change. We may first regard the rise in SRB as an adaptive response to changes in structural factors such as gender bias, normative fertility and available reproductive technologies. According to what Abbott (2001) once called a general linear reality, a view popularized by econometric modeling and rational choice theory, couples simply adjust their reproductive behavior to a new environment characterized by emerging signals, opportunities, and constraints. We then expect an almost imperceptible rise in birth masculinity generated by the gradual change in the causal factors. What we document in this paper, however, is a rather abrupt rise in sex-selective abortions that can be clearly dated. In addition to structural factors, the onset of the rise is therefore likely to have been sparked off by circumstantial factors that precipitated a transformation in reproductive practices—a scenario closer to the cases of sudden outbreaks followed by a gradual diffusion. In this examination of the causal and triggering factors behind demographic transformations, we consider that mechanisms of social change are “triggered under generally unknown conditions or with indeterminate consequences” following the conceptual perspective put forward by Elster (1998) and expanded by path-dependence theorists (Mahoney 2000). This debate on the causal mechanisms behind changes in demographic trends mirrors the discussion on the ultimate and intervening factors at the core of shifts in other demographic behaviors such as labor migration or fertility decline. In the case of the former, sustained migration may be ultimately caused by economic inequality, while the establishment of successful migratory networks represents a very common intervening factor predicating mass migration. As for fertility decline, the question about the respective role of demand and supply factors vs. diffusion mechanisms in explaining a sustained decrease in birth rates remains a matter of continuous discussion. The case of the skewed sex ratio at 3 This figure is calculated as the additional number of excess male births if the SRB had started to increase in 1993 instead of 2003 and plateaued at 113 male births per 100 female births ten years later. Annual estimate of births are taken from United Nations (2015). 3 birth presented here is intended to enrich this debate by providing new materials on the historical determinants of demographic change. In this paper, we take advantage of unique microdata to examine in depth the timing of the changes in the SRB in three different countries. The countries selected here, Albania, Georgia and Vietnam, are characterized by different social, political and economic conditions during the two decades under study. The paper starts with a brief synthesis of what we know of the determinants of rising sex ratios at birth. We then present our data and the methodology followed here to identify turning points in demographic trends. Based on our broken-lines model, we then locate the exact date of the SRB rise using quarterly or monthly figures from the three countries under study.
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